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1.
Int J Biol Macromol ; 268(Pt 1): 131576, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636764

RESUMO

This work aimed to characterize and compare the physicochemical properties of four pulse starches: bean, chickpea, lentil, and pea. Chemical proximate analysis, elemental composition, morphological grain characterization, crystalline structure, thermal analysis, FTIR analysis, and pasting properties were conducted. The proximate analysis shows that these starches have low fat, mineral, and protein content but high amylose values ranging from 29 to 36 % determined by colorimetry. Despite the high amylose content, the starches did not exhibit the typical behavior of an amylose-rich starch, with high peak viscosity and low breakdown and setback. It was found that this behavior was likely due to the large granule size of the ellipsoidal, spherical, and kidney-shaped granules and the high content of some minerals such as Na, Mg, K, Fe, Mn, P, and Si. The study also found that all pulse starches simultaneously contain monoclinic and hexagonal crystals, making them C-type starches. The findings were verified through the Rietveld analyses of X-ray diffraction patterns and differential scanning calorimetry, in which bimodal endothermic peaks evidenced both types of crystals being gelatinized.


Assuntos
Amilose , Reologia , Amido , Amido/química , Amilose/química , Amilose/análise , Fenômenos Químicos , Viscosidade , Difração de Raios X , Lens (Planta)/química , Produtos Agrícolas/química , Cicer/química , Varredura Diferencial de Calorimetria
2.
BMC Genomics ; 25(1): 150, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326752

RESUMO

BACKGROUND: The common house spider Parasteatoda tepidariorum represents an emerging new model organism of arthropod evolutionary and developmental (EvoDevo) studies. Recent technical advances have resulted in the first single-cell sequencing (SCS) data on this species allowing deeper insights to be gained into its early development, but mid-to-late stage embryos were not included in these pioneering studies. RESULTS: Therefore, we performed SCS on mid-to-late stage embryos of Parasteatoda and characterized resulting cell clusters by means of in-silico analysis (comparison of key markers of each cluster with previously published information on these genes). In-silico prediction of the nature of each cluster was then tested/verified by means of additional in-situ hybridization experiments with additional markers of each cluster. CONCLUSIONS: Our data show that SCS data reliably group cells with similar genetic fingerprints into more or less distinct clusters, and thus allows identification of developing cell types on a broader level, such as the distinction of ectodermal, mesodermal and endodermal cell lineages, as well as the identification of distinct developing tissues such as subtypes of nervous tissue cells, the developing heart, or the ventral sulcus (VS). In comparison with recent other SCS studies on the same species, our data represent later developmental stages, and thus provide insights into different stages of developing cell types and tissues such as differentiating neurons and the VS that are only present at these later stages.


Assuntos
Aranhas , Animais , Aranhas/genética , Aranhas/metabolismo , Evolução Biológica , Mesoderma , Células Germinativas , Análise de Sequência de RNA
3.
Curr Opin Gastroenterol ; 39(6): 522-528, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37751393

RESUMO

PURPOSE OF REVIEW: This article aims to provide an up-to-date review of small intestinal bacterial overgrowth (SIBO), including etiology and risk factors, clinical manifestations, diagnostic evaluation for suspected SIBO, and therapeutic options. RECENT FINDINGS: Recent advances in breath testing, capsule and urine-based testing have opened new avenues and improved diagnostic yield of SIBO. Nonantibiotic-based treatment strategies have shown promising results in initial trials. SUMMARY: Small intestinal bacterial overgrowth (SIBO) is a condition defined by the excess bacteria or changes in bacterial composition of the small intestine. These are associated with various gastrointestinal (GI) symptoms such as bloating, abdominal distension, diarrhea, nutrient deficiencies, and even frank weight loss. Small bowel jejunal aspirate of >10 5 CFU/ml has traditionally been considered the gold standard for diagnosis. Glucose and lactulose breath testing have become more common in clinical practice as they are noninvasive, easily accessible, and have lower cost. Treatment focuses on the eradication of excess bacteria in the small bowel and is traditionally done with the use of oral antibiotics. Other emerging therapies may include probiotics, diet manipulation, and prokinetic agents.


Assuntos
Antibacterianos , Intestino Delgado , Humanos , Intestino Delgado/microbiologia , Antibacterianos/uso terapêutico , Lactulose , Bactérias , Diarreia/tratamento farmacológico , Testes Respiratórios/métodos
4.
Cell Biosci ; 13(1): 70, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013648

RESUMO

BACKGROUND: Slit and Robo are evolutionarily conserved ligand and receptor proteins, respectively, but the number of slit and robo gene paralogs varies across recent bilaterian genomes. Previous studies indicate that this ligand-receptor complex is involved in axon guidance. Given the lack of data regarding Slit/Robo in the Lophotrochozoa compared to Ecdysozoa and Deuterostomia, the present study aims to identify and characterize the expression of Slit/Robo orthologs in leech development. RESULTS: We identified one slit (Hau-slit), and two robo genes (Hau-robo1 and Hau-robo2), and characterized their expression spatiotemporally during the development of the glossiphoniid leech Helobdella austinensis. Throughout segmentation and organogenesis, Hau-slit and Hau-robo1 are broadly expressed in complex and roughly complementary patterns in the ventral and dorsal midline, nerve ganglia, foregut, visceral mesoderm and/or endoderm of the crop, rectum and reproductive organs. Before yolk exhaustion, Hau-robo1 is also expressed where the pigmented eye spots will later develop, and Hau-slit is expressed in the area between these future eye spots. In contrast, Hau-robo2 expression is extremely limited, appearing first in the developing pigmented eye spots, and later in the three additional pairs of cryptic eye spots in head region that never develop pigment. Comparing the expression of robo orthologs between H. austinensis and another glossiphoniid leech, Alboglossiphonia lata allows to that robo1 and robo2 operate combinatorially to differentially specify pigmented and cryptic eyespots within the glossiphoniid leeches. CONCLUSIONS: Our results support a conserved role in neurogenesis, midline formation and eye spot development for Slit/Robo in the Lophotrochozoa, and provide relevant data for evo-devo studies related to nervous system evolution.

5.
Materials (Basel) ; 16(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36984148

RESUMO

Ba0.92Ca0.08Ti0.95Zr0.05O3 (BCZT8-5) ceramic materials have been scarcely studied as lead-free piezo/ferroelectrics despite their enhanced Curie temperature (>100 °C) with respect to most studied BCZT compositions. In this work, homogeneous dense BCZT8-5 ceramics with grain size in the range of 20 µm, and optimum ferroelectric, dielectric, and electromechanical performance, were prepared by the mixed oxides route using moderate synthesis (1250 °C-2 h) and sintering (1400 °C-2 h) conditions. Thickness-poled thin disks and monomodal shear plate resonators were used for the determination of piezoelectric coefficients, coupling factors, elastic, and dielectric permittivity coefficients, including all losses, by iterative analysis of impedance curves at resonance. Furthermore, the thermal evolution of the piezoelectric characteristics at resonance was determined to assess the enhanced working range of the ceramics (≈100 °C). Ferroelectric hysteresis loops and strains vs. electric-field butterfly loops were also measured and showed soft behavior with Ec = 2 kV/cm, Pr = 12 µC/cm2 after a maximum applied field of 3 kV was used. The ceramics showed a high endurance of P-E cycles to electrical fatigue up to 107 cycles. Moreover, dielectric properties as a function of temperature were also accomplished and showed nearly normal ferroelectric behavior, characteristic of samples with low crystallographic disorder. Overall, these ceramics showed high sensitivity and higher stability than other currently studied BCZT compositions.

6.
Acta neurol. colomb ; 39(1): 14-19, ene.-mar. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1429569

RESUMO

RESUMEN INTRODUCCIÓN: La neurocisticercosis es una infección del sistema nervioso central causada por el estadio larvario del cestodo Taenia solium, y se estima que puede ocasionar hasta 30% de los casos de epilepsia en los países donde esta parasitosis es endémica. El objetivo de este estudio fue determinar la frecuencia de pacientes que presentaron epilepsia como secuela de neurocisticercosis en un hospital universitario en Popayán. MATERIALES Y MÉTODOS: Se realizó un estudio retrospectivo con todos los pacientes con diagnóstico de neurocisticercosis que ingresaron al Hospital Universitario San José entre enero 2014 y diciembre 2018 que cumplieron los criterios de inclusión. RESULTADOS: Se encontraron 50 pacientes, de estos, 40 (80%) reingresaron, encontrándose que 37 (74%) presentaron epilepsia como secuela. Las edades más afectadas fueron la de 41 a 60 años; 48 (96%) provenían del departamento del Cauca en especial de Mercaderes, y 33 (66%) de área rural. El síndrome convulsivo fue la manifestación clínica de ingreso más frecuente. La TAC fue la técnica de imagen de elección. CONCLUSIÓN: El departamento del Cauca se considera como una de las áreas endémicas para neurocisticercosis en Colombia, y la epilepsia secundaria es un secuela común.


ABSTRACT INTRODUCTION: Neurocysticercosis is an infection of the central nervous system caused by the larval stage of the cestode Taenia solium, it has been estimated to produce up to 30% of the cases in countries where this parasitosis is endemic. The objective of this study was to determine the frequency of patients who presented epilepsy as a sequel of neurocysticercosis in a university hospital in Popayán. MATERIALS AND METHODS: A retrospective study was conducted with all patients with a diagnosis of neurocysticercosis who were admitted to the Hospital Universitario San José between January 2014 and December 2018 who met the inclusion criteria. RESULTS: We found 50 patients, 40 (80%) of which were readmitted and 37 (74%) presented epilepsy as sequela. The most affected age-group was 41 to 60 years; 48 (96%) were from the department of Cauca, especially Mercaderes, and 33 (66%) from rural areas. Convulsive syndrome was the most frequent clinical manifestation on admission. CT was the imaging technique of choice. CONCLUSION: The department of Cauca is considered as an endemic area for neurocysticercosis, and secondary epilepsy was a common consequence.


Assuntos
Neurocisticercose , Epilepsia , Convulsões , Taenia solium , Helmintos
7.
Am Surg ; 89(6): 2413-2426, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35533112

RESUMO

BACKGROUND: Implementation of screening modalities has led to a decreased incidence of colorectal malignancies. Unfortunately, overall incidence has remained unchanged as cases have increased in patients below the suggested screening age. Therefore, we evaluated characteristics and oncological outcomes of malignancies in patients ≤40 years of age. METHODS: Single-center retrospective analysis of prospectively collected data of malignancies in patients ≤40 years evaluated in our institution between 2010 and 2016. Basic descriptors for demographic, clinical, histologic, and genetic data were collected. Disease-free survival (DFS) and 5-year overall survival (OS) were compared for patients between 30-40 years and <30 years. RESULTS: Fifty-six patients ≤40 years were identified, 44 of whom (96.5%) had adenocarcinomas. Most common malignancy location was the rectum (64.3%). Despite aggressive tumor characteristics such as moderate/poor differentiation (88.6%), lymphovascular invasion (26.8%), perineural invasion (21.4%), and advanced tumor stage T3/T4 (60.7%), OS rate was 94.6%. Both age groups had similar oncologic characteristics. There was a trend toward worse OS (2/11 and 1/45, P = .06) but not for DFS (7/11 and 15/43, P = .18) in patients <30 years of age compared to 30-40 years. There were no differences in OS (3/44 vs 0/88, P = .44) or DFS (17/42 vs 3/8, P = .80) between sporadic vs non-sporadic malignancies, respectively. CONCLUSIONS: Patients ≤40 years of age with malignancy have advanced tumor stages and aggressive tumor characteristics at diagnosis. Although there is higher OS risk for patients <30 compared to those aged 30-40 years, no differences were found for DFS between these two groups.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Humanos , Adulto , Estudos Retrospectivos , Neoplasias Colorretais/patologia , Adenocarcinoma/patologia , Reto/patologia , Intervalo Livre de Doença , Estadiamento de Neoplasias , Prognóstico
8.
Evodevo ; 12(1): 7, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078450

RESUMO

BACKGROUND: In the vinegar fly Drosophila melanogaster, the homeodomain containing transcription factor Teashirt (Tsh) appears to specify trunk identity in concert with the function of the Hox genes. While in Drosophila there is a second gene closely related to tsh, called tiptop (tio), in other arthropods species only one copy exists (called tio/tsh). The expression of tsh and tio/tsh, respectively, is surprisingly similar among arthropods suggesting that its function as trunk selector gene may be conserved. Other research, for example on the beetle Tribolium castaneum, questions even conservation of Tsh function among insects. The zinc-finger transcription factor Spalt (Sal) is involved in the regulation of Drosophila tsh, but this regulatory interaction does not appear to be conserved in Tribolium either. Whether the function and interaction of tsh and sal as potential trunk-specifiers, however, is conserved is still unclear because comparative studies on sal expression (except for Tribolium) are lacking, and functional data are (if at all existing) restricted to Insecta. RESULTS: Here, we provide additional data on arthropod tsh expression, show the first data on onychophoran tio/tsh expression, and provide a comprehensive investigation on sal expression patterns in arthropods and an onychophoran. CONCLUSIONS: Our data support the idea that tio/tsh genes are involved in the development of "trunk" segments by regulating limb development. Our data suggest further that the function of Sal is indeed unlikely to be conserved in trunk vs head development like in Drosophila, but early expression of sal is in line with a potential homeotic function, at least in Arthropoda.

9.
Carbohydr Polym ; 246: 116555, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747238

RESUMO

Functional modifications of starch, such as paste properties, retrogradation, water absorption indexes, solubility, and swelling capacity, are induced by the amylose-lipid complex. This research comprehends the study of functional properties of extruded maize starch mixed with fatty acids (stearic acid, oleic acid, and maize oil) and the formation of amylose-lipid complexes. Maize starch with lipids (5 or 10 %), moisture (35 %) was extruded (single screw). Starch granule was modified by extrusion, to a lesser extent at 10 % of lipids, especially stearic acid, which covers starch granule surface. Viscosity decreased meaningfully with stearic acid addition. DSC showed both starch gelatinization enthalpy and amylose-lipid complex enthalpy for stearic or oleic acid, but it was just the first enthalpy for maize oil. X-ray diffraction showed orthorhombic crystals with or without the presence of lipids. Our results indicated that stearic acid yielded the highest amount of amylose-lipid complexes.


Assuntos
Amilose/química , Lipídeos/química , Ácido Oleico/química , Extratos Vegetais/química , Ácidos Esteáricos/química , Zea mays/química , Varredura Diferencial de Calorimetria , Cristalização , Temperatura Alta , Solubilidade , Viscosidade , Água/química , Difração de Raios X
10.
Int J Mol Sci ; 21(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225111

RESUMO

Echiura is one of the most intriguing major subgroups of phylum Annelida because, unlike most other annelids, echiuran adults lack metameric body segmentation. Urechis unicinctus lives in U-shape burrows of soft sediments. Little is known about the molecular mechanisms underlying the development of U. unicinctus. Herein, we overviewed the developmental process from zygote to juvenile U. unicinctus using immunohistochemistry and F-actin staining for the nervous and muscular systems, respectively. Through F-actin staining, we found that muscle fibers began to form in the trochophore phase and that muscles for feeding were produced first. Subsequently, in the segmentation larval stage, the transversal muscle was formed in the shape of a ring in an anterior-to-posterior direction with segment formation, as well as a ventromedian muscle for the formation of a ventral nerve cord. After that, many muscle fibers were produced along the entire body and formed the worm-shaped larva. Finally, we investigated the spatiotemporal expression of Uun_st-mhc, Uun_troponin I, Uun_calponin, and Uun_twist genes found in U. unicinctus. During embryonic development, the striated and smooth muscle genes were co-expressed in the same region. However, the adult body wall muscles showed differential gene expression of each muscle layer. The results of this study will provide the basis for the understanding of muscle differentiation in Echiura.


Assuntos
Anelídeos/crescimento & desenvolvimento , Desenvolvimento Muscular , Actinas/genética , Actinas/metabolismo , Animais , Músculos/metabolismo , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/metabolismo , Transcriptoma
11.
Int J Mol Sci ; 20(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426335

RESUMO

Antistasin, which was originally discovered in the salivary glands of the Mexican leech Haementeria officinalis, was newly isolated from Helobdella austinensis. To confirm the temporal expression of antistasin during embryogenesis, we carried out semi-quantitative RT-PCR. Hau-antistasin1 was uniquely expressed at stage 4 of the cleavage and was strongly expressed in the late stages of organogenesis, as were other antistasin members. In order to confirm the spatial expression of antistasin, we performed fluorescence in situ hybridization in the late stages of organogenesis. The expression of each antistasin in the proboscis showed a similar pattern and varied in expression in the body. In addition, the spatial expression of antistasin orthologs in different leeches showed the possibility of different function across leech species. Hau-antistasin1 was expressed in the same region as hedgehog, which is a known mediator of signal transduction pathway. Hau-antistasin1 is probably a downstream target of Hedgehog signaling, involved in segment polarity signal pathway.


Assuntos
Anticoagulantes/análise , Hormônios de Invertebrado/análise , Sanguessugas/química , Animais , Anticoagulantes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/análise , Proteínas Hedgehog/metabolismo , Hormônios de Invertebrado/genética , Hormônios de Invertebrado/metabolismo , Sanguessugas/embriologia , Sanguessugas/genética , Sanguessugas/metabolismo , Filogenia , Transdução de Sinais
12.
Food Chem ; 298: 124982, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261014

RESUMO

This work studies the physicochemical properties of quinoa flour and isolated starch. Starch in the seed forms clusters rich in amylopectin that are immersed in a matrix with spherical and polygonal shapes in the submicron scale. The isolated quinoa starch is rich in Sulphur and Magnesium. The quinoa flour has a higher content of protein, carbohydrates and lipids than isolated starch. Water absorption and water solubilized indexes of starch exhibited high values that could had originated by the extraction method. The broad peaks found for the X-ray patterns of isolated quinoa starch indicate that amylose and amylopectin are composed by nanocrystals, according to the PDF-4+2019 software. The viscosity of isolated starch had a higher value than flour; therefore, the quinoa starch could be used as a thickener in different formulations with the advantage of keeping a significant presence of minerals which are important to the human health.


Assuntos
Chenopodium quinoa/química , Farinha/análise , Análise de Alimentos/métodos , Amido/química , Amilopectina/química , Amilose/análise , Microscopia Eletrônica de Varredura , Minerais/análise , Sementes/química , Sementes/ultraestrutura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise , Amido/ultraestrutura , Temperatura , Viscosidade , Água/química , Difração de Raios X
13.
Food Chem ; 283: 83-91, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722929

RESUMO

This work focused in the study of the changes on the physicochemical properties of isolated jícama starch (IJS), and IJS added with 0.15, 0.20, 0.30% Ca(OH)2 w/w. including: the structural, morphological, chemical, vibrational, pasting, rheological, and thermal characteristics. K, Ca, Na, and P were found in IJS. X-ray patterns, which showed that nanocrystals form the IJS according to the PDF-4 simulation. The functional properties were affected by the Ca inclusion, which originated electrostatic interactions. The gelatinization temperatures shifted to high values and exhibited an unfolding. The calculation of the IR absorption coefficient (ß) of the gelatinized samples as a function of the Ca2+ for the C-OH showed that the Van der Waals interaction causes the changes in the rheological-mechanical properties. The SEM images demonstrated that starch without alkali exhibited a porous network structure, while the starch with lime exhibited flakes and porous network. The gels of Jicama starch with Ca(OH)2 showed a viscoelastic behavior (G' > G″) with a reduction of their elastic module.


Assuntos
Hidróxido de Cálcio/química , Pachyrhizus/metabolismo , Amido/química , Amilose/metabolismo , Microscopia Eletrônica de Varredura , Nanopartículas/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Viscosidade , Difração de Raios X
14.
J Exp Zool B Mol Dev Evol ; 330(6-7): 341-350, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30280505

RESUMO

The Forkhead box (Fox) gene family is an evolutionarily ancient gene family named after the Drosophila melanogaster forkhead gene (fkh). Fox genes are highly conserved transcription factors critical for embryogenesis and carcinogenesis. In the current study, we report a whole-genome survey of Fox genes and their expression patterns in the leech Helobdella austienesis. Phylogenetic analysis suggests that some Fox genes of leeches are correlated with other Lophotrochozoa and vertebrate Fox genes. Here we have performed semiquantitative reverse transcription polymerase chain reaction and whole-mount in situ hybridization of Fox genes throughout the embryonic development of H. austinensis. We found that each one of the leech Fox genes (FoxA1, FoxA3, FoxC, FoxL2, FoxO1, and FoxO2) is expressed in a specific set of cells or tissue type. From Stages 9-11, Hau-FoxA1 was expressed in the foregut of the anterior region, and Hau-FoxL2 was expressed in mesodermal muscle fiber. Hau-FoxA3 was temporally expressed in the ventral neuroectoderm. At Stage 11, Hau-FoxC was expressed in the foregut. Hau-FoxO genes have a ubiquitous expression. Our results provide more insight on the evolutionary linkage and role of the Fox gene function in Bilateria.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Sanguessugas/embriologia , Sanguessugas/metabolismo , Animais , Ectoderma/embriologia , Ectoderma/metabolismo , Embrião não Mamífero/metabolismo , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma/embriologia , Mesoderma/metabolismo , Filogenia , Sequenciamento do Exoma
15.
Genes Genomics ; 40(7): 747-753, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29934812

RESUMO

The earthworm Perionyx excavatus is a species highly capable of bidirectional regeneration. Pair-rule genes are thought to have an ancestral function in arthropod segmentation. However, orthologs in annelids (i.e. Capitella teleta) do not exhibit segmental expression in the ectoderm or mesoderm. Their role in regeneration is currently unclear. Here, we report the expression profile of primary pair-rule genes (Pex-EvxA, Pex-EvxB, Pex-RuntA, Pex-RuntB, Pex-Hes1A, Pex-Hes1B, Pex-Hes4A, and Pex-Hey) found in P. excavatus using semi-quantitative reverse transcription-polymerase chain reaction. Our results indicated these genes showed variable expression during bidirectional regeneration. Six of these genes might play diverse and potentially critical roles in head and/or tail regeneration.


Assuntos
Padronização Corporal/genética , Oligoquetos/genética , Regeneração/genética , Sequência de Aminoácidos/genética , Animais , Conservação dos Recursos Naturais , Ectoderma/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Oligoquetos/crescimento & desenvolvimento
16.
Dev Genes Evol ; 227(6): 415-421, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29188382

RESUMO

snail gene family members are zinc-finger transcription factors with key roles in morphogenesis. Involvement of snail family genes in mesoderm formation has been observed in insects and mammals. The snail genes are also involved in cell motility, neural differentiation, cell fate, survival decision, and left-right identity. The functions of snail genes have been studied primarily among ecdysozoans and deuterostomes, with relatively little work carried out in lophotrochozoans. In this study, we isolated two snail homologs (Hau-snail1 and Hau-snail2) from the leech Helobdella austinensis. We characterized the temporal and spatial expression patterns of these two genes by semi-quantitative RT-PCR and in situ hybridization. The expression of Hau-snail1 and Hau-snail2 correlates with ventral nerve cord (VNC) development, segmental mesoderm, and with a ring of cells that comes to lie at the base of the leech proboscis, respectively, showing similarity to the divergent expression of duplicated snail genes in polychaetes. Our results do not support the function of lophotrochozoan snail genes in mesoderm specification.


Assuntos
Sanguessugas/crescimento & desenvolvimento , Sanguessugas/genética , Fatores de Transcrição da Família Snail/genética , Transcriptoma , Sequência de Aminoácidos , Animais , Clonagem Molecular , Duplicação Gênica , Sanguessugas/metabolismo , Filogenia , Análise de Sequência de DNA , Fatores de Transcrição da Família Snail/química , Fatores de Transcrição da Família Snail/metabolismo
17.
Dev Genes Evol ; 227(4): 245-252, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28699036

RESUMO

Genes of the twist family encode bHLH transcription factors known to be involved in the regulation and differentiation of early mesoderm. Here, we report our characterization of Hau-twist, a twist homolog from the leech Helobdella austinensis, a tractable lophotrochozoan representative. Hau-twist was expressed in segmental founder cells of the mesodermal lineage, in subsets of cells within the mesodermal lineage of the germinal plate, in circumferential muscle fibers of a provisional integument during segmentation and organogenesis stages and on the ventral side of the developing proboscis. Thus, consistent with other systems, our results suggest that twist gene of the leech Helobdella might function in mesoderm differentiation.


Assuntos
Sanguessugas/crescimento & desenvolvimento , Sanguessugas/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Embrião não Mamífero/metabolismo , Sanguessugas/citologia , Mesoderma/citologia , Mesoderma/metabolismo , Filogenia
18.
Front Zool ; 14: 60, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29299039

RESUMO

BACKGROUND: The need for the adaptation of species of annelids as "Evo-Devo" model organisms of the superphylum Lophotrochozoa to refine the understanding of the phylogenetic relationships between bilaterian organisms, has promoted an increase in the studies dealing with embryonic development among related species such as leeches from the Glossiphoniidae family. The present study aims to describe the embryogenesis of Alboglossiphonia lata (Oka, 1910), a freshwater glossiphoniid leech, chiefly distributed in East Asia, and validate standard molecular biology techniques to support the use of this species as an additional model for "Evo-Devo" studies. RESULTS: A. lata undergoes direct development, and follows the highly conserved clitellate annelid mode of spiral cleavage development; the duration from the egg laying to the juvenile stage is ~7.5 days, and it is iteroparous, indicating that it feeds and deposits eggs again after the first round of brooding, as described in several other glossiphoniid leech species studied to date. The embryos hatch only after complete organ development and proboscis retraction, which has not yet been observed in other glossiphoniid genera. The phylogenetic position of A. lata within the Glossiphoniidae family has been confirmed using cytochrome c oxidase subunit 1 (CO1) sequencing. Lineage tracer injections confirmed the fates of the presumptive meso- and ectodermal precursors, and immunostaining showed the formation of the ventral nerve system during later stages of development. Further, the spatiotemporal expression of an EF-hand calcium-binding protein Calsensin ortholog was characterized, which showed a specific pattern in both the ventral and peripheral nervous systems during the later stages. CONCLUSIONS: Our description of the embryonic development of A. lata under laboratory conditions provides new data for further comparative studies with other leech and lophotrochozoa model organisms. Moreover, it offers a basis for the establishment of this species as a model for future "Evo-Devo" studies.

19.
South Med J ; 109(5): 277-81, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27135722

RESUMO

OBJECTIVES: The African American population has a higher prevalence of advanced colon adenomas when compared with non-Hispanic whites and Hispanics, but the risk in other black populations has not been evaluated. Although the Afro-Caribbean population is a significant demographic segment in some regions of the United States, the data are limited on the prevalence of colon adenomas in this group and there is no comparison with a non-Hispanic white population. The objective of our study was to compare the prevalence of adenomas in Afro-Caribbean versus non-Hispanic white populations. METHODS: A total of 880 Afro-Caribbean patients and 1828 non-Hispanic white patients undergoing their first screening colonoscopy between January 2008 and August 2014 was included in the study. RESULTS: A total of 2708 patients met entry criteria for the study. The adenoma detection rate among Afro-Caribbeans was 29% and 31% among non-Hispanic whites. There was no statistically significant difference in the prevalence of adenomas in the two groups (P = 0.28), and the rate of advanced adenomas also was similar in both groups (8.6% in Afro-Caribbeans, 9.2% in non-Hispanic whites; P = 0.60). A multivariate analysis also found no difference in the occurrence of adenomas (P = 0.60) or advanced adenomas (P = 0.99) between Afro-Caribbeans and non-Hispanic whites. CONCLUSIONS: We found a similar adenoma detection rate and advanced adenoma prevalence among Afro-Caribbeans and non-Hispanic whites undergoing their first screening colonoscopy. As such, the Afro-Caribbean population may not have the same risk of colorectal neoplasia as what has been described for African Americans. Based on these results, it is appropriate to initiate colorectal cancer screening for Afro-Caribbeans at age 50 as recommended for non-Hispanic whites.


Assuntos
Adenoma/diagnóstico , Negro ou Afro-Americano/estatística & dados numéricos , Colonoscopia , Neoplasias Colorretais/diagnóstico , População Branca/estatística & dados numéricos , Fatores Etários , Região do Caribe/etnologia , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia , Estados Unidos/epidemiologia
20.
Eur J Gastroenterol Hepatol ; 27(8): 974-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26011236

RESUMO

OBJECTIVE: The aim of this study was to evaluate the influence of BMI on colonic neoplasia in average-risk patients aged between 40 and 59 years, analyzed by sex. METHODS: A total of 4443 patients aged between 40 and 59 years undergoing a first-time screening or average-risk colonoscopy were included in this study. Data on demographics, smoking, and BMI were collected and correlated to the presence of adenomas and advanced adenomas. RESULTS: We evaluated 1197 colonoscopies in patients aged between 40 and 49 years, and 3246 in those aged between 50 and 59 years. Among men between 40 and 49 years, increasing BMI [odds ratio (OR)=1.05, 95% confidence interval (CI): 1.00-1.09] and BMI of at least 27 (OR=1.95, 95% CI: 1.15-3.29) were predictors of adenomas. Younger men with a BMI of at least 27 were more likely to have proximal adenomas (OR=2.23, 95% CI: 1.14-4.37) but not advanced adenomas. There was no relation between BMI and adenomas in younger women. Among women aged between 50 and 59 years, increasing BMI (OR=1.03, 95% CI: 1.01-1.05) and a BMI of at least 24 (OR=1.43, 95% CI: 1.06-2.94) was found to be correlated with adenomas, and increasing BMI was also found to be associated with proximal adenomas (OR=1.67, 95% CI: 1.13-2.45). Among men aged between 50 and 59 years, there was no relation between BMI and adenomas, but there was a positive correlation for advanced adenomas (OR=1.05, 95% CI: 1.002-1.09). Among women aged between 50 and 59 years, BMI was not predictive of advanced adenomas. CONCLUSION: The association between BMI and adenoma differs by age and sex. If BMI is utilized to refine screening practices for colorectal cancer, its influence on sex and age should be taken into account.


Assuntos
Adenoma/epidemiologia , Índice de Massa Corporal , Neoplasias do Colo/epidemiologia , Obesidade/epidemiologia , Adenoma/patologia , Adulto , Distribuição por Idade , Fatores Etários , Distribuição de Qui-Quadrado , Neoplasias do Colo/patologia , Colonoscopia , Detecção Precoce de Câncer/métodos , Feminino , Florida/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Razão de Chances , Seleção de Pacientes , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Fumar/efeitos adversos , Fumar/epidemiologia
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